The present invention relates to vehicle roofs and in particular to roofs for convertible vehicles.
In conventional convertible roofs for vehicles, the roof which is made from a flexible material is located on a frame. The frame consists of a pair of main beams mounted longitudinally of the vehicle on either side of the passenger compartment, the forward ends of the main beams being interconnected by a transversely extending canopy rail which is adapted to sealingly engage and be latched to the windscreen header when the roof is erected, and two or three bows which span the main beams at longitudinally spaced locations. The flexible roof material is attached at the forward end to the canopy rail and at the rearward end to the vehicle body. The roof lining may be attached to the intermediate bows by webbing.
The main beams are hinged and linkage mechanisms are provided on either side of the roof frame, to control folding of the roof as it is moved from an erected to a lowered position and vice versa. Power means, for example an electric motor or hydraulic ram may be associated with the linkage mechanisms in order to power movement of the roof between its erected and lowered position.
Hitherto, such roofs have been latched manually, lever mechanisms being provided on each main beam, adjacent forward ends thereof. These lever mechanisms include latch means for engagement of the windscreen header, so that the latch means may be engaged with the windscreen header and the lever mechanism actuated to clamp and seal the canopy rail of the roof frame to the windscreen header.
When the roof is erected, it is necessary to tension the flexible roof material, so that it will not be creased and the material will not flap when the vehicle is in motion. In order to achieve this, the roof frame is normally designed so that when it is unfolded and the flexible material untensioned, the canopy rail will stand off the windscreen header and must be pulled down onto the header before it can be latched thereto. The action of pulling the canopy rail down onto the header tensions the roof material.
With powered roofs, it would also be an advantage if the latching mechanism could also be powered so that it can operate automatically. However, in order to do this effectively, the canopy rail of the roof frame must abut or be located in close proximity to the windscreen header when the roof frame is unfolded and the roof material untensioned. The conventional tensioning method cannot consequently be used in such circumstances.
The present invention provides an alternative tensioning means for a convertible vehicle roof of the type disclosed above, which permits the use of automatic powered latching means.